Pneumatic conveyer



Jan. 14, 1947. J. HIGGINS PNEUMATIC CONVEYER Filed Feb. 15, 1945 via:

' mmyroa v65 .5 fggflS Patented Jan. 14, 1947 UNITED STATES PATENTOFFICE PNEUMATIC CQNVEYER 'ohnL. Higgins, Chicago, Ill.

Appiication February 15, 1945, Serial No. 578,056

4 Claims.

1 This invention relates to pneumatic conveyer apparatus and will bedescribed as applied to an ash conveyer apparatus such as us d by largesteam power plants. However, it will be'appreciated that the inventionhas application to other pneumatic conveyer apparatus wherein similarproblems are encountered and continuous, conveyor action is desired.

In many pneumatic ash conveys-rs such as used by power plants, the ashesmust be taken from the ash pits located under the boilers to receivertan-ks mounted at considerable heights at distant points from the powerplants, where the ashes may be disposed of by gravity into dump cars ona railroad siding or sluiccd through a discharge line into a dump. Thisarrangement necessitates long conveyer pipe lines extending upwardlytoward the receiver.

The conveyer apparatus is used periodically when the boiler room helperor ash man is instructed to empty the ash pit. In the conventional formof pneumatic conveyor apparatus utilizing a single receiver tank andvacuum system, the vacuum system operates on an on cycle of about twominutes and an off cycle of one minute, in order to provide a timeinterval for removing ashes in the receiver hopper tank which is undervacuum when being filled. During the off time interval, this receiverhopper is emptied.

When the vacand then the operation resumes. uum, is shut ofi for thisreason, the ash in the upwardly extending conveyer line drops downwardlyand packs in the pipe making resumption of the ash flow difficult andwasting the work already expended on the ashes.- is augmented by thecontinued piling of ashes in the inlet openin of the pipe line if theash man continues his labors when the vacuum is shut oil.

It is the particular object of the present invention to avoid thedimculties of the oiT and on system of operation and to provide meanswhereby the continuous operation of the pneumatic conveyor is permitted.

Other objects and benefits will be disclosed in the following desc ionsand Fig, l is an elevation view partly in section of thereceiver-separator apparatus employing the invention; and

Fig, 2 is a top plan view thereof.

Now referring to the drawing: I designate, by the numeral it in dashlines, the course of the incoming ash line which, of course. will startat a level far below the receiver apparatus, The numeral E designatesthe tangential inlet pipe of this ash line to the receiver i2. This is acon- This difliculty rawing in which:

ventional type of receiver wherein'the ashes are led into the receiverin a tangential manner as is well understood in the art. Under thereceiver i2 is the conventional conical hopper tank l3 which at times isclosed by a swinging door I4 abutting inclined opening in a cupola inletiii of another coacting bin hopper tank It. The bin hopper tank it has aconventional swinging discharge gate H which may be arranged todischarge directly into a dump car, storage tank, or it may be arrangedto connect with a sluice pipe to carry ashes into a convenient dump. Ontop of the closed bin to is an upstanding pipe l9 connected to aconventional Venturi pipe 20 which in turn is connected to a tangentialpipe 2! leading into a dust separator 22. The dust separator is emptiedin a conventional manner through the pipe 23. A steam pipe 24 connectsto the primary injector chamber 25 having nozes 26 coacting with theventuri 2!). When steam is permitted to enter the chamber 25 by means ofan electrically controlled valve 21, which may be located at'anydesirable location, the jets of steam from the nozzles 26 coactin withthe venturi 2% cause a suction in the bin 16 which closes the spring.opened valve to, which is normally open to provide a vent to theatmosphere, and the suction therefrom is transmitted through theswinging door it to create a suction in thereceiver 52 which draws ashesthrough the lines I10 and H and deposits them in the conical hopper tank23 of the receiver ttancl" through the door :4 into the bin tank it.Thus far the use of the venturi it to create a suction in the lines Hiand H is a conventional means to convey ashes in pipe lines except thatthe receiver l2 has been separated from the bin it by the hopper tankI3,

When this pneumatic removal of ashes has continued for sufiicient timeto nearly fill the bin IS, the electrically controlled valve 21 is shutofi automatically through the automatic time switch 8 thus stopping theflow of steam through the venturi 2e, and before this how of steam iscompletely stopped, another electrically controlled valve 28 in the pipeline 29 connected. to the supply line 24, is automatically opened by theswitch 34 and electrical connections 35 and the steam emerging from thisline 29 through the nozzle 39 coacting with another venturi 3| continuesto create suction in the receiver I2 through the pipe 32. When thissuction is applied through the pipe 32 to the receiver E2, the suctionthus created closes the swinging door Hi and the ashes from the lines itand H are deposited in the hopper tank I3 of the receiver it. Duringthis period of time, the ashes in the bin tank It are discharged bygravity upon release of the spring controlled valve t8, then valve 28 isshut 01f, the valve 2! opened, and the Venturi 20 picks up the vacuumload to thus continuously draw ashes through the lines In and II.

Thus I avoid the disadvantage of the ashes falling back in lines Ill andII, save the energy created by the inertia of the ashes in these lines,and remove ashes continuously. When the vacuum in the receiver l2created by the Venturi 25] is transmitted through the pipe 32 to theVenturi 3|, the hinged valve 33 on the end of the Venturi 3| closes andefiectively cuts off the connection between the venturi 20 and 3|. Bythis arrangement, it will be appreciated that I have combined dualVenturi operations to avoid the difficulties and disadvantages when asingle venturi and receiver is used and provide a continuous ash removalconveyer.

Having thus described my invention, I now claim as new? 1. In apneumatic ash conveyer, a conveyer pipe line from an ash pit extendingupwardly, a hopper bin tank having a swinging discharge gate mounted ata height considerably above the ash pit, a receiver attached to theconveyer pipe having a dump hopper and swinging discharge gate mountedabove the bin tank with the dump hopper arranged to discharge into thebin tank, a dual Venturi suction device mounted on the bin tank with onesuction device arranged to create suction in the receiver, thearrangement of the suction connections and the swinging discharge gatesproviding means to draw ashes through the receiver into the bin tankwith one of the suction devices and to draw ashes through the receiverand into the receiver hopper by the other suction device, and means tocontrol the operation of the two suction devices to permit dumpingof theashes in the bin while continuing to draw ashes from the conveyer lineinto the receiver hopper, thereby providing a continuous ash conveyingsystem.

.2. Ina conveyer of the character described, the combination ofreceiving and discharge chambers having means of communicationtherebetween adapted for the discharge of material from said receivingchamber into said discharge chamber, said receiving chamber beingadapted to be connected with a fluid conduit for supply of materialthereto, means for closing said communication, means connected with thedischarge chamber for creating suction in said receiving and dischargechambers for sucking material into the receiving chamber for dischargetherefrom into the discharge chamber, and means for creating suction inthe receiving chamber upon closing of the communication between thechambers to continue the supply of material to the receiving chamber. I

3. In a conveyer of the character described, the combination ofreceiving and discharge chambers having means of communicationtherebetween and adapted for the passage of material from said receivingchamber to said discharge chamber, said receiving chamber being adaptedto be connected with a fluid conduit for supply of material thereto,means for closing said communication therebetween, dual suction devicesone of which is connected with the discharge chamber for creatingsuction therein and causing material to be drawn into the receivingchamber and discharged therefrom into the discharge chamber, and theother suction device being connected with the receiving chamber andhaving means for automatically creating suction therein upon the closureofcommunication between the chambers to continue the supply of materialto said receiving chamber while the material is being withdrawn from thedischarge chamber.

4. In a conveyer of the character described, the combination of a hopperbin tank having a swinging discharge gate, a receiver adapted to beconnected with a fluid conduit for supply of material thereto, saidreceiver having a dump hopper and a swinging discharge gate and mountedabove the bin tank and arranged to discharge into said tank, dualVenturi suction devices connected with the bin tank with one suctiondevice arranged to creat suction in the receiver, the arrangement of thesuction connections and the swinging discharge gates providing means todraw material through the receiver into the bin tank by the action ofone'of the suction devices and to draw material into the receiver to thedischarge gate in closed position by the other suction device, and meansfor controlling the operation of the suction devices to permit dumpingof the material in the tank while continuing to draw material into thereceiver substantially in a continuous manner.

JOHN L. HIGGINS.

